SNAP CONNECTION HINGE Filed Feb. 16, 1968 INVENTOR. Paw A. Zarzza'zzra ATTORNEY United States Patent O" 3,497,908 SNAP CONNECTION HINGE Paul A. Zamarra, Lake Road, Far Hills, NJ. 07931 Filed Feb. 16, 1968, Ser. No. 706,076 Int. Cl. Ed 1/06 US. Cl. 16-171 3 Claims ABSTRACT OF THE DISCLOSURE Interfoliated members of a hinge are maintained in tight but not stiff pivotal connection by spring bias resulting from the snap action seating of a pivot element in a socket that is constituted, in part, by a resilient detent which is displaced by the pivot element as it enters the socket and which thereafter remains under tension in pressure contact with a portion of the pivot element and holds it in the socket.

BACKGROUND The present invention relates to the art of hinge construction, and in particular to hinges in which the component parts are assembled in service relation by a snap action connection effected through forced engagement of interfoliated elements arranged to fulcrum on the pivot axis of the hinge. An example of the general type of hinge with which the present invention is concerned is illustrated in US. Patent 2,570,341.

In the general type of prior art hinge represented by said patent, the wing members are connected by engagement of pivot elements on one wing member with sockets provided in resilient extensions of the other wing member; the pivot elements being forced inwardly through the open outer ends of one or more guide grooves in the socket-carrying extensions, entering between the extensions and forcing them apart against their bias sufiiciently to allow passage of the pivot elements to abut the closed inner ends of the grooves. The inner ends of the grooves form sockets in which the rounded pivot elements are seated with a snap action resulting from their initial expansion, as described in the patent, column 2, lines 36-50. When the pivot elements are fully seated, the expanding force on the socket-carrying extensions is removed, and although the respective wing members are connected in hinged relation the connection is not tight and the grooves present passages through which the rounded pivot elements may pass unimpeded.

SUMMARY OF THE INVENTION The present invention provides a hinge in which the wing members are pivotally connected by snap action engagement of interfoliated extensions of the wings, which extensions fulcrum on the pivot axis of the hinge. Certain of the extensions are resilient, and during their interengagement with the other extensions are placed under tension which provides a spring bias that maintains a tight but not stiff connection between the wing members at all times. The bias is constant; thereby providing automatic take-up action which compensates for wear.

The present invention further provides a hinge connection between interfoliated parts, certain ones of which mount pivot elements that seat in sockets in the others, in which the pivot elements pass to their receiving sockets through guide grooves having means operative by the pivot elements during their passage to place the socket-carrying extensions under a tension that imparts to them a spring bias forcibly holding the pivot elements seated in their sockets.

The present invention provides also a hinge connection between interfoliated members in which a pivot element 3,497,908 Patented Mar. 3, 1970 on one member is snap seated in a socket of an adjacent member by means of a resilient detent that constitutes a part of the socket and which is displaced by the pivot element as it enters the socket.

DRAWINGS FIG. 1 is a plan view of the hinge wing members of the present invention assembled as a two-part container.

FIG. 2 is a hinge-side elevation of the assembled and closed container of FIG. 1.

FIG. 3 is a fragmentary sectional view on line 3-3 of FIG. 1.

FIG. 4 is a fragmentary sectional view on line 4-4 of FIG. 3.

FIG. 5 is a fragmentary plan view illustrating details of a pivot element unit of the hinge.

FIG. 6 is a fragmentary plan view illustrating details of a socket unit of the hinge.

FIG. 7 is substantially a sectional view taken axially through a connected hinge.

FIG. 8 is a fragmentary plan view of the hinge in process' of assembly connection.

FIG. 9 is a view similar to FIG. 8, but showing the hinge assembly fully connected.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the preferred embodiment of the present invention a pair of hinge wing members 10 and 11, here shown as identical walls of a two-part container of molded plastic material generally similar in shape to the container of the aforesaid Patent 2,570,341, are pivotally connected by interfoliated extensions that fulcrum on the pivot axis of the hinge. Two connections are provided, and because of the fact that the two sections of the container are identical, being produced in the same mold, the component parts of each hinge connection are reversed relative to the other. Because of this relationship, detailed description of one will serve for both.

Particular reference is made to the hinge connection at the right in FIG. 1. The wing member 10 is of molded plastic material and is formed with a hinge unit comprising a pair of integral extensions 12 projecting from a side edge thereof and to the same extent. These extensions are rectangular in cross section and are sufficiently resilient to provide a spring bias resisting their mutual deflection toward or away from each other under the application of force tending to press them together or apart. As shown best in FIGS. 3 and 4, the outer side face of each resilient extension 12 is recessed to provide a guide channel or groove 13 closed at its inner end and open at its outer end. The groove is semicircular in cross section and is rounded at its closed inner end portion to present a semispherical socket 14.

The companion Wing member 11 is formed with a hinge unit comprising a pair of integral extensions 15 projecting laterally from a side edge thereof in parallel relation and spaced apart a distance suflicient to receive slidably between them the unit comprising the extensions 12 on the wing member 10. The inner side faces of the extensions 15 are formed with oppositely extending semispherical bosses constituting pivot elements 16 that seat in the sockets 14 when the hinge is connected. These bosses and the grooves 13 are complemental.

The pivot element extensions 15 are thicker in cross section than the socket extensions 12 and therefore do not have the resiliency of the socket extensions. They are not subject to deflection during connection of the hinge.

An important feature of the present invention is the means :by which each pivot element is caused to snap seat in its receiving socket and is held therein under pressure of a spring biased detent operated by the pivot element during entry in its socket.

This means comprises a detent 17, here shown as a rounded pimple or nub, located on the bottom of the groove in the path of travel of the socket element as it enters the groove. The diameter of detent 17 at its base is approximately one-third of the base diameter of the pivot element 16 with which it is associated, and its height is approximately half the height of the pivot element. Furthermore, the detent is located on the longitudinal median of its groove in its open outer end as shown in FIG. 3. The relative dimensions of each associated pivot element, socket, and detent are such that, when the hinge is connected, the pivot element swivels in its socket on the pivot axis of the hinge, and the detent constitutes a minor but effective wall portion of the socket in rolling line contact with the rounded surface of the pivot element.

The hinge is connected by placing the rounded pivot elements 16 of one unit in the open ends of the guide grooves 13 in the other unit in contact with their detents 17 and forcing the units together with the pivot elements riding inwardly over the detents to seat in the sockets 14. The extensions 15 of the unit which carries the pivot elements straddle the extensions of the unit which carries the sockets, and as the pivot elements ride in over the detents 17 the socket-carrying extensions are deflected laterally toward each other against the spring bias resulting from their resiliency; thus placing the socketcarrying extensions under a tension which effects a snap action seating of the pivot elements when they enter their sockets. After the pivot elements are seated the tension on the deflected socket-carrying extensions 12 remains constant, but to a lesser extent. So long as the hinge is connected, the pivot elements 16 are engaged against the detents with a constant force tending to deflect the socket-carrying extensions laterally in opposition to their bias, thus maintaining a tight but not stiff connection in which the existing spring bias provides automatic take up action.

The detents 17 function also as means operative to hold the pivot elements seated in their sockets. When the pivot elements are seated the detents constitute obstructions barring passage of the pivot elements longitudinally of the grooves, thus preventing fortuitous disconnection of the hinge.

It is within the purview of this invention that, if desired, the extensions could he resilient and the .extensions 12 rigid either separately or joined as one, and that the grooves and sockets could be carried by the extensions 15 with the pivot elements 16 located on the extensions 12.

I claim:

1. A snap connection hinge comprising, a pair of wing members each having a unit pair of lateral extensions from a side edge thereof and arranged in parallel spaced relation, the unit pair of extensions on one wing member straddling the unit pair of extensions on the other wing member when the hingle is connected, oppositely facing pivot elements on one unit pair of extensions,

' oppositely facing sockets for the pivot elements carried by the other unit pair of extensions, each socket-carrying extension having therein a guide groove open at its outer end to receive a pivot element and leading to its socket, a detent in the open end of the guide groove and deflectible by a pivot element'when passing through the guide groove to its stocket, one of said unit pairs of extensions being resilient, deflection of the detent acting to place the component extensions of the resilient pair under tension imparting oppositely acting spring biases thereto, and each detent constituting an obstruction barring accidental egress of a socket seated pivot element outwardly through its associated groove.

2. In the structure of claim 1, said pivot elements being rounded bosses, said sockets being complemental thereto, and said detents having spring biased line contact pressure engagement with the pivot elements while they are seated in their associated sockets.

3. In the structure of-claim 1, said grooves opening at the same ends of the socket-carrying extensions.